1. Field of the Invention
This invention relates to methods for sealing a closure member around a substrate, and to closure members suitable for use in such methods. The invention is particular useful for forming closures around conduits, especially joints between conduits, e.g. splices in telephone cables.
2. Summary of the Prior Art
Many methods are known for sealing a closure member around a substrate. Often, there is difficulty in ensuring adequate conformance of the closure member to the substrate, because the substrate has an irregular surface and/or because the closure member must seal around two or more substrates, for example when an enclosure is to be formed around a "one-in, two-out" cable splice. To overcome this difficulty, it is well known to use closure members which are heat-shrinkable or elastomeric; it has also been proposed to use inflatable closure members, but these have not gained commercial acceptance. The difficulty of obtaining a satisfactory seal is particularly acute when the substrate, after being covered, is maintained under superatmospheric pressure, e.g. a splice in a pressurised telephone cable.